Protective device for a measuring apparatus

ABSTRACT

A protective device for a measuring apparatus which can be arranged on a tripod includes a housing having a threaded hole and a threaded pin, where the threaded hole is disposed in a housing lower side of the housing and the threaded pin is disposed in a housing upper side of the housing. The protective device further includes an airbag and a filling device having at least one gas-filled gas container, a control device, and an energy source. A connecting line connects the airbag and the filling device for gas exchange. The airbag surrounds a cylindrical interior space in an inflated state.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority of International Application No.PCT/EP2019/067549, filed Jul. 1, 2019, and European Patent Document No.18182811.2, filed Jul. 11, 2018, the disclosures of which are expresslyincorporated by reference herein.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to a protective device for a measuringapparatus.

Measuring apparatuses, such as total stations, laser scanners, 2-Dlayout devices and rotary laser levels are used inside and outside forleveling, marking and measuring tasks. Measuring apparatuses aregenerally secured on a tripod, which is set up inside or outside at thedesired position. In this context, there can be accidents in which themeasuring apparatus and the tripod tip over and fall onto the underlyingsurface or onto surrounding objects. Sensitive measuring apparatuses maybe irreparably damaged. On the one hand, this gives rise to costs forthe repair or replacement of the measuring apparatus and, furthermore,there is no measuring apparatus available until the measuring apparatushas been repaired or replaced.

To avoid damage to measuring apparatuses due to falls, protectivedevices with an airbag are known. KR 101474718 B1 discloses a protectivedevice of this kind for a measuring apparatus designed as a totalstation. If the apparatus tips over, an airbag designed as a cushion isinflated, placing itself between the underlying surface and themeasuring apparatus and thereby preventing a direct impact of themeasuring apparatus on the underlying surface. The protective device isdesigned as a separate accessory, which is arranged between themeasuring apparatus and the tripod. The protective device comprises ahousing, four airbags, a filling device having a gas-filled gascontainer, a control device and an energy source as well as a connectingline, which connects the airbags to the filling device. The four airbagsare arranged folded up in the housing of the protective device, whereineach of the four airbags is assigned to one angular region. With the aidof a sensor device, the tipping direction of the measuring apparatus andthe associated airbag are determined. The gas container for filling theairbags is connected to the airbags via a line and is set up close tothe tripod.

The protective device known from KR 10141741718 B1 for a measuringapparatus has the disadvantage that four airbags are required and thefilling device is arranged outside the housing. This leads to aprotective device which can hinder the user in operating the measuringapparatus, and the user can stumble over the gas container, which is setup next to the tripod, and cause the measuring apparatus to tip over. Ifthe measuring apparatus is subject to an impact in the transitionalregion between two adjacent airbags, there is a risk that the measuringapparatus will tip or roll off the airbag and be damaged despite theprotective device.

The object of the present invention is to develop a protective devicefor a measuring apparatus which is secured on a tripod. The protectivedevice is intended to protect all the components of the measuringapparatus from damage. At the same time, the protective device should beof as compact design as possible and should hinder the user as little aspossible, ideally not at all, in operating the measuring apparatus.

According to the invention, it is envisaged that the airbag surrounds acylindrical interior space in the inflated stale. The protective deviceaccording to the invention is used to protect measuring apparatuseswhich are secured on a tripod. Owing to the fact that the measuringapparatus is secured on a tripod, shocks to the tripod and/or themeasuring apparatus lead to tipping over of the tripod. Generally, theentire arrangement comprising the tripod and the measuring apparatustips over one tripod leg or two tripod legs, and the measuring apparatusapproaches the underlying surface in an arc. The regions of themeasuring apparatus which strike the underlying surface first can beeasily identified and protected with the aid of the airbag.

The airbag is designed in such a way that, in the inflated state, itsurrounds a cylindrical interior space in which the measuring apparatusis located. Since, when tipping over with the tripod, the measuringapparatus suffers the impact on its side, the airbag offers adequateprotection. The airbag surrounds the measuring apparatus and distributesthe energy introduced during the impact: during this process, as littleas possible energy is transferred to the measuring apparatus. Thecylindrical interior space can be composed of a plurality of cylindricalsections, and the shape of the cylindrical interior space is matched tothe shape of the measuring apparatus.

The airbag preferably has a first stabilization chamber, an impactchamber and a second stabilization chamber, wherein the firststabilization chamber and the impact chamber are connected for gasexchange, and the impact chamber and the second stabilization chamberare connected for gas exchange. The term impact chamber is used todenote a chamber of the airbag via which energy is introduced on impactwith an underlying surface, and the term stabilization chambers is usedto denote chambers of the airbag which stabilize the shape of theairbag. During a tipover, energy is introduced via the impact chamber,and the energy introduced is then distributed and dissipated in theairbag. During this process, as little as possible energy is transferredto the measuring apparatus located in the cylindrical interior space ofthe airbag. The impact chamber is of annular design and protects theregions of the measuring apparatus which touch the underlying surfacefirst during an impact by the measuring apparatus. The impact chamber isconfigured in such a way that it projects relative to the firststabilization chamber and relative to the second stabilization chamberon the outside of the airbag.

As a particular preference, the impact chamber has a ring width which isgreater than a first width of the first stabilization chamber andgreater than a second width of the second stabilization chamber. Bymeans of the ring width of the impact chamber, it is possible to ensurethat the impact chamber projects relative to the first stabilizationchamber and relative to the second stabilization chamber on the outsideof the airbag.

The first stabilization chamber preferably has a plurality of firstsubchambers, wherein adjacent first subchambers are connected for gasexchange. By means of the number and geometry of the first subchamberswhich form the first stabilization chamber, it is possible to influencehow energy transfer of the energy introduced during the impact takesplace in the airbag. During this process, as little as possible energyis transferred to the measuring apparatus located in the cylindricalinterior space of the airbag.

The impact chamber preferably has a plurality of first impactsubchambers, wherein adjacent first impact subchambers are connected forgas exchange. By means of the number and geometry of the first impactsubchambers which form the impact chamber, it is possible to influencehow energy transfer of the energy introduced during the impact takesplace in the airbag. During this process, as little as possible energyis transferred to the measuring apparatus located in the cylindricalinterior space of the airbag.

The second stabilization chamber preferably has a plurality of secondsubchambers, wherein adjacent second subchambers are connected for gasexchange. By means of the number and geometry of the second subchamberswhich form the second stabilization chamber, it is possible to influencehow energy transfer of the energy introduced during the impact takesplace in the airbag. During this process, as little as possible energyis transferred to the measuring apparatus located in the cylindricalinterior space of the airbag.

The airbag preferably has a filling chamber, wherein the firststabilization chamber and the filling chamber are connected for gasexchange. The gas does not flow directly into the first stabilizationchamber but flows initially into the filling chamber and, from there,into the first stabilization chamber. The filling chamber distributesthe gas uniformly in the first stabilization chamber and bridges thepath between the housing of the protective device and the firststabilization chamber of the airbag.

As a particular preference, the filling chamber has a plurality ofsubchambers. In order to accelerate the filling of the airbag with gas,the gas container can have a plurality of connecting lines, whichconnect the gas container to the subchambers of the filling chambers.

As a particular preference, the airbag additionally has a further impactchamber and a third stabilization chamber, wherein the secondstabilization chamber and the further impact chamber are connected forgas exchange, and the further impact chamber and the third stabilizationchamber are connected for gas exchange. In the case of large measuringapparatuses or measuring apparatuses with an irregular shape, an airbagwith a further impact chamber and a third stabilization chamber offersthe possibility of introducing the energy into the airbag during theimpact via a plurality of impact chambers and distributing it moreuniformly. The energy introduced into the impact chamber and the furtherimpact chamber is distributed with the aid of the gas in the airbag.

As a particular preference, the further impact chamber has a pluralityof second impact subchambers, wherein adjacent second impact subchambersare connected for gas exchange. By means of the number and geometry ofthe second impact subchambers which form the impact chamber, it ispossible to influence how energy transfer of the energy introducedduring the impact takes place in the airbag. During this process, aslittle as possible energy is transferred to the measuring apparatuslocated in the cylindrical interior space of the airbag.

As a particular preference, the third stabilization chamber has aplurality of third subchambers, wherein adjacent third subchambers areconnected for gas exchange. By means of the number and geometry of thethird subchambers which form the third stabilization chamber, it ispossible to influence how energy transfer of the energy introducedduring the impact takes place in the airbag. During this process, aslittle as possible energy is transferred to the measuring apparatuslocated in the cylindrical interior space of the airbag.

In a preferred embodiment, a valve, which can be switched between anopen state and a closed state by the control device, is provided in theconnecting line. The gas introduced into the airbag can escape slowlyvia the valve after the triggering of the airbag. As an alternative, theairbag can be emptied by removing the gas container from the protectivedevice, thereby enabling the gas to escape more quickly from the airbag.The materials used for the airbag are generally not absolutelyimpermeable to gas, and a small portion of the gas can diffuse to theoutside through the airbag.

Exemplary embodiments of the invention are described hereinafter withreference to the drawings. It is not necessarily intended for these toillustrate the exemplary embodiments to scale; instead, the drawings,where conducive to elucidation, are executed in schematic and/orslightly distorted form. It should be taken into account here thatvarious modifications and alterations relating to the form and detail ofan embodiment may be undertaken without departing from the generalconcept of the invention. The general concept of the invention is notlimited to the exact form or the detail of the preferred embodimentshown and described hereinafter or limited to subject matter that wouldbe limited compared to the subject matter claimed in the claims. Forgiven design ranges, values within the limits mentioned shall also bedisclosed as limiting values and shall be usable and claimable asdesired. For the sake of simplicity, identical reference numerals areused hereinafter for identical or similar parts or parts havingidentical or similar function.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a protective device, which is arranged between a measuringapparatus and a tripod;

FIGS. 2A and 2B show the protective device of FIG. 1 ;

FIGS. 3A and 3B show the protective device of FIG. 1 with an inflatedairbag in a view from above (FIG. 3A) and in a side view (FIG. 3B);

FIGS. 4A and 4B show the airbag of FIGS. 3A and 3B, which is constructedfrom a plurality of chambers, with the connection between a firststabilization chamber and an impact chamber (FIG. 4A) and the connectionbetween the impact chamber and a second stabilization chamber 34 (FIG.4B); and

FIGS. 5A and 5B show an alternative airbag for the protective device ofFIG. 1 .

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a protective device 10, which is arranged between ameasuring apparatus 11 and a tripod 12. Normally, measuring apparatusesare secured directly on a tripod. For this purpose, measuringapparatuses have a standardized threaded hole, into which a standardizedthreaded pin of the tripod is screwed.

The term “measuring apparatus” includes all apparatuses for measurementof phenomena and properties that are not accessible. Examples ofmeasuring apparatuses are total stations, laser scanners, 2-D layoutdevices and rotary laser levels.

FIGS. 2A and 2B show the protective device 10 of FIG. 1 . The protectivedevice 10 comprises a housing 13, an airbag 14, a filling device 15 anda connecting line 16, which connects the airbag 14 and the fillingdevice 15 to one another. The filling device 15 comprises a gascontainer 17, which is filled with a gas, a control device 18, whichcontrols the filling device 15 and the connecting line 16, and an energysource 19, which supplies the energy required to inflate the airbag 14by means of the filling device 15. The term “control device” includesall components which perform open-loop control, closed-loop controland/or monitoring of the operation of the protective device 10. Thecontrol device 18 comprises, for example, a microcontroller and anacceleration sensor, which detects the tipping of the measuringapparatus 11.

The housing 13 consists of a plurality of housing sections, which aredesigned as a housing lower side 21, as a housing upper side 22, aslower lateral surfaces 23 and as upper lateral surfaces 24. A threadedhole 25, which is screwed onto the threaded pin of the tripod 12, isprovided in the housing lower side 21, and a threaded pin 26, onto whichthe threaded hole in the measuring apparatus 12 is screwed, is providedin the housing upper side 22. In order to make a distinction, thethreaded hole 25 and the threaded pin 26 of the protective device 10 aredenoted below as the first threaded hole and the first threaded pin, thethreaded hole in the measuring apparatus 12 is denoted as the secondthreaded hole, and the threaded pin of the tripod is denoted as thesecond threaded pin.

The housing 13 is divided into a lower interior space and an upperinterior space. The lower interior space is bounded by the housing lowerside 21, the lower lateral surfaces 23 and a partition surface 27, andthe upper interior space is bounded by the partition surface 27, theupper lateral surfaces 24 and the housing upper side 22. The lowerinterior space accommodates the filling device 15 with the gas container17, the control de-vice 18 and the energy source 19. In the exemplaryembodiment, the gas container 17 is inserted into the housing 13 fromthe outside and can simply be replaced with a new gas container; as analternative, the gas container can be installed in a fixed manner in thehousing. The upper interior space accommodates the airbag 14 in thefolded state. The upper lateral surfaces 24 are designed as foldingsurfaces, which are folded out in use, thus enabling the airbag 14 to beinflated by means of the filling device 15. The protective device 10 canbe switched on and off by means of a switch 28.

FIGS. 3A and 3B show the airbag 14 of the protective device 10 in theinflated state. In this case, FIG. 3A shows the airbag 14 in a view fromabove, and FIG. 3B shows the airbag 14 in a side view.

FIG. 3A shows the protective device 10, which is arranged between themeasuring apparatus 11 and the tripod 12. The inflated airbag 14 of theprotective device 10 surrounds a cylindrical interior space, in whichthe measuring apparatus 11 is arranged and protected from damage. Theshape of the interior space is as far as possible matched to theexternal geometry of the measuring apparatus 11.

The airbag 14 comprises a plurality of annular chambers, which aredesigned as a first stabilization chamber 32, as an impact chamber 33and as a second stabilization chamber 34. As the airbag 14 is filled,the gas flows into the first stabilization chamber 32 and, from there,into the impact chamber 33 and then into the second stabilizationchamber 34. The first stabilization chamber 32 is connected to theimpact chamber 33 for gas exchange, and the impact chamber 33 isconnected to the second stabilization chamber 34 for gas exchange.

The term impact chamber is used to denote a chamber of the airbag 14 viawhich energy/force is introduced on impact with an underlying surface,and the term stabilization chambers is used to denote chambers of theairbag 14 which stabilize the shape of the airbag 14. In this context, adistinction is made between a first stabilization chamber and a secondstabilization chamber. As the airbag 14 is filled, the firststabilization chamber is filled with gas at a time before the secondstabilization chamber.

In constructing the airbag 14, consideration must be given to the tactthat the airbag has to be fully inflated within a short time in order toprotect the measuring apparatus 11 during a tipover. On the other hand,the airbag 14 must have a shape which distributes the energy introducedinto the impact chamber 33 during the fall by equalizing the pressurevia the gas in the airbag. The adaptation of the shape of the airbag 14is accomplished by dividing the first stabilization chamber 32, theimpact chamber 33 and/or the second stabilization chamber 34 intosubchambers. The subdivision can be accomplished with the aid of tucks,for example, which reduce the cross-sectional area at the transitionbetween adjacent subchambers.

In the exemplary embodiment, the first stabilization chamber 32comprises four first subchambers 32A, 32B, 32C, 32D, wherein adjacentfirst subchambers are connected for gas exchange. In the exemplaryembodiment, the impact chamber 33 comprises four impact subchambers 33A,33B, 33C, 33D, wherein adjacent impact subchambers are connected for gasexchange. In the exemplary embodiment, the second stabilization chamber34 comprises three second subchambers 34A, 34B, 34C, wherein adjacentsecond subchambers are connected for gas exchange. For their part, thesecond subchambers 34A, 34B, 34C can be divided again into secondsubchambers.

As the airbag 14 is filled, the gas flows into the first stabilizationchamber 32 and, from there, into the impact chamber 33 and then into thesecond stabilization chamber 34. In order to allow rapid inflation ofthe airbag 14, the first stabilization chamber 32, the impact chamber 33and the second stabilization chamber 34 are connected by connectingpassages 35A, 35B, 35C, 35D. The cross-sectional area of the connectingpassages is matched to the volume of the gas used.

The exemplary embodiment in FIGS. 3A and 3B shows an airbag having animpact chamber. As an alternative, the airbag can have two impactchambers or more than two impact chambers. The number of impact chamberswhich an airbag has depends on the size, the weight, the fall height andthe shape of the measuring apparatus which is to be protected by theairbag.

FIGS. 4A and 4B show the connection between the first stabilizationchamber 32 and the impact chamber 33 (FIG. 4A) and the connectionbetween the impact chamber 33 and the second stabilization chamber 34(FIG. 4B).

The filling of the airbag 51 takes place via the connecting passages35A, 35B, 35C, 35D, which connect the first stabilization chamber 32 andthe impact chamber 33 and connect the impact chamber 33 and the secondstabilization chamber 34. Moreover, the connecting passages 35A, 35B,35C, 35D allow gas exchange between the impact chamber 33 and the firstand second stabilization chambers 32, 34. The energy introduced via theimpact chamber 33 during the impact is distributed via the gas in theair-bag 14.

FIGS. 5A and 5B show an airbag 51 which can replace the airbag 14 in theprotective device 10. The airbag 51 comprises a plurality of annularchambers, which are designed as a filling chamber 52, as a firststabilization chamber 53, as an impact chamber 54, as a secondstabilization chamber 55, as a further impact chamber 56 and as a thirdstabilization chamber 57. In order to make a distinction, the impactchamber 54 is referred to as the first impact chamber, and the furtherimpact chamber 56 is referred to as the second impact chamber. Theairbag 51 surrounds a cylindrical interior space 58.

In the case of large measuring apparatuses or measuring apparatuses withan irregular shape, the airbag 51 with the impact chamber 54 and thefurther impact chamber 56 offers the possibility of introducing theenergy into the airbag 51 during the impact via the two impact chambers54, 56 and distributing it more uniformly in the airbag 51. The energyintroduced into the impact chamber 54 and the further impact chamber 56is distributed with the aid of the gas in the airbag 51. The firststabilization chamber 53, the second stabilization chamber 55 and thethird stabilization chamber 57 serve to stabilize the airbag 51.

As the airbag 51 is filled, the gas initially flows out of the gascontainer 17 into the filling chamber 52, from there into the firststabilization chamber 53, from there into the impact chamber 54, fromthere into the second stabilization chamber 55, from there into thefurther impact chamber 56 and from there into the third stabilizationchamber 57. The first stabilization chamber 53 is connected to theimpact chamber 54 for gas ex-change, the impact chamber 54 is connectedto the second stabilization chamber 55 for gas exchange, the secondstabilization chamber 55 is connected to the further impact chamber 56for gas exchange, and the further impact chamber 56 is connected to thethird stabilization chamber 57 for gas exchange.

The invention claimed is:
 1. A protective device for a measuringapparatus which can be arranged on a tripod, comprising: a housinghaving a threaded hole and a threaded pin, wherein the threaded hole isdisposed in a housing lower side of the housing and the threaded pin isdisposed in a housing upper side of the housing; an airbag; a fillingdevice having at least one gas-filled gas container, a control device,and an energy source; and a connecting line which connects the airbagand the filling device for gas exchange; wherein the airbag surrounds acylindrical interior space in an inflated state of the airbag; whereinthe airbag has a first stabilization chamber, an impact chamber, and asecond stabilization chamber, wherein the first stabilization chamberand the impact chamber are connected for gas exchange, and wherein theimpact chamber and the second stabilization chamber are connected forgas exchange.
 2. The protective device as claimed in claim 1, whereinthe impact chamber has a ring width which is greater than a first widthof the first stabilization chamber and is greater than a second width ofthe second stabilization chamber.
 3. The protective device as claimed inclaim 1, wherein the first stabilization chamber has a plurality offirst subchambers and wherein adjacent first subchambers of theplurality of first subchambers are connected for gas exchange.
 4. Theprotective device as claimed in claim 1, wherein the impact chamber hasa plurality of first impact subchambers and wherein adjacent firstimpact subchambers of the plurality of first impact subchambers areconnected for gas exchange.
 5. The protective device as claimed in claim1, wherein the second stabilization chamber has a plurality of secondsubchambers and wherein adjacent second subchambers of the plurality ofsecond subchambers are connected for gas exchange.
 6. The protectivedevice as claimed in claim 1, wherein the airbag has a filling chamberand wherein the first stabilization chamber and the filling chamber areconnected for gas exchange.
 7. The protective device as claimed in claim6, wherein the filling chamber has a plurality of subchambers.
 8. Theprotective device as claimed in claim 1, wherein the airbag has afurther impact chamber and a third stabilization chamber, wherein thesecond stabilization chamber and the further impact chamber areconnected for gas exchange, and wherein the further impact chamber andthe third stabilization chamber are connected for gas exchange.
 9. Theprotective device as claimed in claim 8, wherein the further impactchamber has a plurality of second impact subchambers and whereinadjacent second impact subchambers of the plurality of second impactsubchambers are connected for gas exchange.
 10. The protective device asclaimed in claim 8, wherein the third stabilization chamber has aplurality of third subchambers and wherein adjacent third subchambers ofthe plurality of third subchambers are connected for gas exchange. 11.The protective device as claimed in claim 1, wherein a valve is disposedin the connecting line and wherein the valve is switchable between anopen state and a closed state by the control device.
 12. The protectivedevice as claimed in claim 1, wherein the impact chamber is configuredsuch that the impact chamber projects relative to the firststabilization chamber and relative to the second stabilization chamberon an outside of the airbag.